At the beginning of the year, Savannah had $90 in savings and saved an additional $10 each week thereafter. Isaac started the year with $50 and saved $20 every week. Let S represent the amount of money Savannah has saved t weeks after the beginning of the year and let I represent the amount of money Isaac has saved t weeks after the beginning of the year. Graph each function and determine the who has more money saved after 6 weeks.
